North Korea is demanding that South Korea send back 12 North Korean restaurant workers who came to the South in 2016, saying such a move would demonstrate Seoul's willingness to improve relations.
The North's statement on Saturday came a week after Seoul said it would look more closely into the circumstances surrounding the women's arrival following a media report that suggested some of them might have been brought to the South against their will.
Earlier in the week, North Korea canceled a high-level meeting with the South over US-South Korean military exercises and threatened to call off a planned summit between its leader, Kim Jong Un, and President Donald Trump.
The cancellation cooled what had been an unusual flurry of diplomatic moves from Pyongyang.